异形桥塔独塔斜拉桥设计与分析

发布时间：2018-04-15 18:09

本文选题：独塔斜拉桥 + 异形桥塔　；参考：《西南交通大学》2015年硕士论文

【摘要】：桥塔作为斜拉桥的标志,其构造多种多样,异形桥塔也越来越多,而异形桥塔的受力较常规桥塔复杂,导致其计算分析相对困难。论文以雅安大兴二桥独塔斜拉桥初步设计方案为依托,初步设计跨径布置为50m+188m+122m+48m,桥塔采用多横梁梭形形式。通过建立全桥空间梁单元有限元模型,对全桥进行静力、稳定性及抗震分析和设计优化,再借助主梁节段实体单元模型,对其横桥向受力进行计算分析。论文首先介绍独塔斜拉桥相关的应用背景、设计理论和发展前景,然后总结该类异形桥塔独塔斜拉桥的建模相关事项。利用该有限元模型,分别计算分析结构在施工阶段、成桥运营阶段的应力、变形与稳定性,得出在施工、运营过程中桥例结构安全可靠,施工阶段结构稳定性逐渐降低。通过分析混凝土时变效应对结构应力的影响,得到其影响对桥例结构不可忽略。采用反应谱分析法和时程分析法对全桥结构在地震作用下的承载能力进行计算得到桥塔底部结构抗震能力不足。针对这一问题,通过计算分析在主梁和桥墩之间设置阻尼器情况下的桥塔底部结构内力和塔顶位移,得出合理设置阻尼器使塔底结构弯矩、剪力和塔顶位移均减小20%左右,使作用于结构的地震作用明显降低。运用有限元软件ANSYS建立桥例主梁节段的实体单元模型,通过分别计算分析改变横隔板预应力钢束的锚固位置和横隔板厚度得到锚固位置变化对主梁结构主拉应力的影响较大。将横隔板预应力钢束锚固在靠近箱梁底板位置的方式能降低主梁的主拉应力。
[Abstract]:As the symbol of cable-stayed bridge, the structure of the tower is varied and the special-shaped tower is more and more. The stress of the special-shaped tower is more complicated than that of the conventional bridge tower, which leads to the difficulty of calculation and analysis.Based on the preliminary design scheme of Ya'an Daxing second Bridge single tower cable-stayed bridge, the preliminary design span is 50m 188m 122m 48m, and the bridge tower adopts multi-beam spindle form.By establishing the finite element model of the space beam of the whole bridge, the static, stability, seismic analysis and design optimization of the whole bridge are carried out, and then the transverse force of the bridge is calculated and analyzed with the help of the solid element model of the main girder segment.This paper first introduces the application background, design theory and development prospect of single tower cable-stayed bridge, and then summarizes the related matters of modeling of this kind of special-shaped cable-stayed bridge with single tower.Using the finite element model, the stress, deformation and stability of the structure in the construction stage and the operation stage of the bridge are calculated and analyzed respectively. It is concluded that the bridge example structure is safe and reliable in the construction and operation process, and the structural stability decreases gradually in the construction stage.By analyzing the influence of time-varying effect of concrete on structural stress, it is concluded that the influence of time-varying effect of concrete can not be ignored.The response spectrum analysis and time history analysis are used to calculate the bearing capacity of the whole bridge structure under earthquake action. The results show that the seismic capacity of the bottom structure of the bridge tower is insufficient.In order to solve this problem, through the calculation and analysis of the internal force and the top displacement of the bottom structure of the bridge tower under the condition of installing dampers between the main beam and the pier, it is concluded that the reasonable installation of the damper can reduce the bending moment, shear force and displacement of the tower top by about 20%.The seismic action acting on the structure is obviously reduced.The finite element software ANSYS is used to establish the solid element model of the main girder segment of the bridge. The influence of the change of the anchoring position and the thickness of the transverse partition plate on the main tensile stress of the main girder structure is obtained by calculating and analyzing respectively the anchoring position of the prestressed steel bundle and the thickness of the transverse partition plate.The main tensile stress of the main beam can be reduced by anchoring the prestressed steel bundle near the bottom plate of the box girder.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U448.27

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